tree ad5831b52b38ca8157dd3ba4e5dfb75768bd372f
parent 1c9904297451f558191e211a48d8838b4bf792b0
author Eric Paris <eparis@redhat.com> 1303431800 -0700
committer Eric Paris <eparis@redhat.com> 1303763081 -0400

SELINUX: Make selinux cache VFS RCU walks safe

Now that the security modules can decide whether they support the
dcache RCU walk or not it's possible to make selinux a bit more
RCU friendly.  The SELinux AVC and security server access decision
code is RCU safe.  A specific piece of the LSM audit code may not
be RCU safe.

This patch makes the VFS RCU walk retry if it would hit the non RCU
safe chunk of code.  It will normally just work under RCU.  This is
done simply by passing the VFS RCU state as a flag down into the
avc_audit() code and returning ECHILD there if it would have an issue.

Based-on-patch-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Eric Paris <eparis@redhat.com>